It's really hard for anybody -- truly rest easy until we get a sense of whether the suspects had any ties to an international terrorist group. That may still want to do us harm. ABC's Martha Raddatz as I said in Washington this morning Martha how will a federal investigators. Try to figure out whether there is involvement from an outside organized terror group. What they'll basically do -- is work backwards they want to look at the pattern of life particularly that older brother who they really are focusing on. The older brother Tara -- was in Russia. Last year. For six months we have no idea why he was there. They're suspicious about why he was there did he get any sort of training did he get any sort of guidance did he get any sort of financing. For a terror attack. So they'll start there what investigators also -- -- and really the whole national security intelligence establishment. In the United States. Is go back and see if they missed any self. We have been told again and again there was no so called chatter they didn't hear anybody talking about a potential attack they didn't think any sort of attack was. Was imminent or -- -- or even really possible at the Boston Marathon that -- they'll go back now and -- what they miss. But basically they do with detective work. In reverse and also see what their plans were for the future. You know they seized a couple of computers they're gonna go through those computers are gonna scrubbed those computers they're gonna see. If those Brothers were possibly radicalized in some way through the Internet. -- through overseas connection. A lot of work to be done but what. I wonder is the scarier scenario for investigators is scarier to think that -- says it won't young men -- lone wolves who were radicalized by the viral Islamist. Online philosophy or -- -- scared I think that they are actually connected. To some sort of shadowy terror. I I think they're both pretty frightening possibilities. And and we can see the results of that what no matter what happened and no matter how. Or what their motives were. The lone -- scenario the United States is -- -- is frightened about that how many others might be motivated by what happened this week. But any sort of connection overseas -- I think is a bit more frightening. First of all it has ramifications. If the United States finds -- smoking gun overseas if they know there's a connection. Particularly. Any sort of state sponsored terrorism and how do you respond. What is the US respond. I talk to one official who said his nightmare. Would have been or would be if say Iran was connected there's absolutely no evidence of that. But then what would they do what what they do -- has -- what was connected what would they do all these different scenarios and that's what. Is pretty frightening to government officials. And the geopolitical ramifications of that with the accident here and complex Martha -- -- so great to have your perspective on this Saturday morning a big news morning. Thank you very much.

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